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Restrictions on the use of long-chain per- and polyfluoralkyl substances (PFASs) has led to substitutions with short-chain PFASs. This study investigated the presence of four short-chain PFASs and twenty-four long-chain PFASs in leachate and sediment from ten Norwegian landfills, including one site in Svalbard, to assess whether short-chain PFASs are more dominant in leachate. PFASs were detected in all sites. Short-chain PFASs were major contributors to the total PFAS leachate concentrations in six of ten landfills, though not in Svalbard...

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Three treatment systems for wastewater from two landfills, one active and one closed, and an industrial location including a quarry have been monitored continuously for over a decade. The wastewater from the active landfill is infiltrated through an extensive unsaturated zone into groundwater and subsequently into a large river system. The wastewater from the closed landfill is treated in a constructed wetland (CW) and the industrial low-grade wastewater in filter dams. The treatment systems operate well with the specific wastewaters, high-concentration leachate from waste in infiltration systems, low-concentration leachate in constructed wetlands, and wastewater from inert waste in filter dams. The landfilling of organic waste was restricted to low limit values for more than a decade ago, but it is hard to see any changes in leachate due to changes in waste landfilling regulations. The heavy carbon stable isotope 13C is useful in tracing landfill leachate and to evaluate dilution into other water bodies. The adding of P to the aeration pond treating low-concentration leachate did not help in the removal of N; on the contrary, the concentration of ammonia was sharply decreased when the adding of P was discontinued.

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The fast development of laboratory methods has revealed increased amounts of trace concentrations of pharmaceuticals and personal care products (PPCP) in waste waters in the Czech Republic. This paper focuses on the expected costs to solve this problem by quaternary treatment of waste water based on activated carbon filtration. The one-time investment costs in 155 wastewater treatment plants (WWTPs) with a capacity of over 10 000 population equivalent (PE) would represent an amount of around 300 million EUR. The increase in end-user operat-ing costs would be 0.4 EUR/m3, which would mean a 15% increase in water and sewage costs. A sociological survey showed that most respondents (65%) would agree with an increase in price but only by 10%. Currently the cost of the qua-ternary treatment of wastewater is based primarily on estimates. Therefore changes in legislation leading to stricter limits and an increase in the efficiency of wastewater treatment should be preceded by additional applied research.

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This study describes the first Norwegian microbial source tracking (MST) approach for water quality control and pollution removal from catchment run-off in a nature-based treatment system (NBTS) with a constructed wetland. The applied MST tools combined microbial analyses and molecular tests to detect and define the source(s) and dominant origin(s) of faecal water contamination. Faecal indicator bacteria Escherichia coli and host-specific Bacteroidales 16 s rRNA gene markers have been employed. The study revealed that the newly developed contribution profiling of faecal origin derived from the Bacteroidales DNA could quantitatively distinguish between human and non-human pollution origins. Further, the outcomes of the MST test have been compared with the results of both physicochemical analyses and tests of pharmaceutical and personal care products (PPCPs). A strong positive correlation was discovered between the human marker and PPCPs. Gabapentin was the most frequently detected compound and it showed the uppermost positive correlation with the human marker. The study demonstrated that the NBTS performs satisfactorily with the removal of E. coli but not PPCPs. Interestingly, the presence of PPCPs in the water samples was not correlated with high concentrations of E. coli. Neither has the latter an apparent correlation with the human marker.

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Many cities and urban areas are located in flood plains because land is fertile and flat which is suitable for agriculture and urban development. Rivers provide water supply for domestic, industrial and irrigation uses; they also provide convenient means for navigation, transportation and communication. Cities have large percentage of impervious areas that prevent effective infiltration of rainfall into soil. To have successful flood control and flood risk management, we should consider not only hydraulic and engineering aspects but also socio-economic and environment aspects. Flood management should have involvement of various stakeholders including concerned authorities such as urban planners, civil and water resources engineers, civil disaster defence authorities, health and social services, etc. The best flood mitigation measures from all main points of view – social, economic and environmental are natural water retention measures. Natural water retention measures cover a diversity of measures that are implemented by different sectors or considered in different planning processes dealing with water, food risk management, biodiversity protection, climate change adaptation or urban planning. Some of these measures aim to directly modify the ecosystem, while others focus on changes of practice of economic operators. The paper presents natural water retention measures suitable for application in urban areas.

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Water quality problems in Norway are caused mainly by high phosphorus (P) inputs from catchment areas. Multiple pollution sources contributes to P inputs into watercourses, and the two main sources in rural areas are agricultural runoff and discharge from on-site wastewater treatment systems (OWTSs). To reduce these inputs, Constructed wetlands (CWs) treating catchment runoff have been implemented in Norway since early 1990s. These CWs have been proven effective as supplements to agricultural best management practices for water quality improvements and therefore there are more than 1000 CWs established in Norway at present. This study aims to present some overall data on the present status of CWs treating catchment runoff in Norway, and in particular recent results of source tracking and retention of sediments and total phosphorus (TP) in a model, full-scale, long-term operated CW, which in practice treats runoff from a typical rural catchment with pollution from both point and diffuse sources. Nutrient contributions from agricultural runoff and OWTSs have been quantified in eight catchments, while the source tracking and retention of sediments and P has been studied in the model CW. P runoff in the catchments was largely affected by precipitation and runoff situation, and varied both throughout the year (every single year) and from one year to another. Annual TP contribution that origins from OWTSs was in general limited, and only 1 % in the catchment of the model CW. Monthly contribution, however, was higher than 30 % during warm/dry season, and cold months with frost season. For the purpose of source tracking study, faecal indicator bacteria (reported in terms of Escherichia coli - E. coli) and host-specific 16S rRNA gene markers Bacteroidales have been applied. High E.coli concentrations were well associated with high TP inputs into waterbodies during dry or/and cold season with little or no agriculture runoff, and further microbial source tracking (MST) tests proved human contribution. There are considerable variations in retention of sediments and TP in the CW between the years, and the annual yearly retention was about 38 % and 16 %, respectively. During the study period, the average monthly retention of sediments and TP was 54 % and 32 %, respectively. E. coli concentrations were also reduced in water passing the CW. The study confirmed that runoff from agricultural areas is the main P source in watercourses, however, discharges from OWTS can also be of great importance for the water quality, especially during warm/dry- and cold/frosty periods. Small CWs treating catchment runoff contribute substantially to the reduction of sediments, TP and faecal indicator bacteria transport into water recipients.

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Norwegian constructed wetlands (CWs) that treat domestic wastewater are classified as horizontal subsurface flow constructed wetlands (HSFCWs). Over the years of continuous performance, the HSFCWs operating under cold climate conditions have shown a high and stable treatment efficiency with regard to the removal of organic matter (>90 % BOD), nutrients (>50 % N and >90 % P) and microbes (>99 % bacteria). The majority of Norwegian HSFCWs are categorised as small (<50 pe) on-site, decentralised wastewater treatment systems. The Norwegian systems consist of three fundamental elements: a septic tank, a pre-filter (i.e. an aerobic vertical flow biofilter) and a horizontal flow saturated filter/wetland bed. The first, primary treatment step begins in the septic tank from which effluents are pre-treated in the second step occurring in the pre-filter/biofilter section and further in the third, final step taking place in the filter bed/HSFCW. The first and third treatment steps are quite common in systems with CWs, but the pre-treatment in biofilter(s) is mainly known from Norway. The main purpose of using the pre-treatment phase is to supply air during the cold season, to enhance nitrification processes, and to reduce the load of organic matter before entering the filter/wetland bed. If constructed and maintained correctly, the biofilters alone can remove 90 % BOD and 40 % N. Various filter/CW beds have been introduced for treatment of domestic wastewater (as complete or source-separated streams) in Norway, but the most common feature is the use of specific filter media for high phosphorus (P) removal. A few Norwegian municipalities also have limits with respect to nitrogen (N) discharge, but the majority of municipalities use 1.0 mg P/l as the discharge limit for small wastewater treatment systems. This particular limit affects the P retention lifetime of the filter media, which varies from system to system depending on the filter media applied, the type of wastewater treated, and the system design and loading rates. An estimated lifetime of filter media with regard to P removal is approximately 15–18 years for a filter/CW bed of a single household. After completing the lifetime, the filter media is excavated and replaced with new/fresh materials, allowing the system to operate effectively for another lifespan. Since the exploited media are P-rich materials, the main intention is their reuse in a safe and hygienic way, in which P could be further utilised. Therefore, the Norwegian systems can represent a complex technology combining a sustainable technique of domestic wastewater treatment and a bio-economical option for filter media reuse. This is a quite challenging goal for reclamation and recycling of P from wastewater. Thus, there are some scenarios of reusing the P-rich filter media as a complementary P fertiliser, a soil amendment or a conditioner, provided the quality is acceptable for utilisation in agriculture. Alternatively, the filter media could be reused in some engineering projects, e.g. green roof technology, road screening or construction of embankments, if the quality allows application in the environment. The core aspect of the reuse options is the appropriate quality of the filter media. As for the theoretical assumption, it should not be risky to reuse the P-rich media in agriculture. In practice, however, the media must be proven safe for human and environmental health prior to introducing into the environment.

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Nutrients for food production are traditionally extracted from natural resources, most importantly as nitrogen from the air, and phosphorous from limited mineral resources. They can also be recovered and recycled from human waste products. There is generally a low P status in the world’s soils, while Norwegian soils are rich in phosphorous. Most recyclable P is in human and animal waste products as wastewater and manure, but also municipal solid waste and more recently, organic waste contain a considerable amount of P that ideally can be utilized.

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Polluted soil locations as well as solid waste landfills can be significant sources of potential pollution of the soil, biomass and both the surface and the groundwater. The management of the polluted soil sites in Norway is regulated according to the health risk related limits of target pollutants, focusing primarily on the presence of the eight key heavy metals and ten groups of organic pollutants in the top 1 m of soil, and to a risk based evaluation of the site leaching. The landfills are evaluated in a same way but the fate of the pollutants originating there is also supposed to be monitored using tracers. Tracing the sources and their effects can be complicated and expensive. Diffuse discharges of leachate from landfills are difficult to monitor since they typically originate under large volumes of waste. Typically, no adequate sampling or monitoring equipment is installed prior to when the landfilling operation begins. Groundwater flows are also hard to predict both in space and time and generally their scale asks for a very complex sampling strategy. The exact amount of water entering a landfill is also difficult to control and monitor due to typically large and heterogeneous areas involved, with differing evapotranspiration, infiltration and runoff characteristics. In this report we present cases of heavy metal pollution originating from a former oil production equipment scrapyard and case studies of complex pollution coming from traditional municipal solid waste landfills. Evaluation of tracers and the geostatistical modelling of their distribution and concentrations in order to evaluate the location of sources and the extent of pollution (plumes) was used. The analyses are cost reduction optimized. A total of 7 landfills were sampled over several years. The most effective tracer for the leachate description seems to be the carbon-13 isotope (13C). At some polluted sites the pollutants can be carried a great length due to wind erosion. Geostatistical methods and the software Grapher were applied. It became obvious that the public health focused risk assessments become difficult when the inflicted areas are large.

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The plant P uptake from sewage sludge and biochar was investigated in pot experiments after manipulating the waste pH by mixing with acidic compost leachate or high pH concrete waste at two levels. Available P was measured both wit passive DGT samplers and by P uptake in rye grass during three harvests. The treatment pH in waste was about 4 after waste was mixed with leachate, and 11.5 with concrete waste. The pH in the pot during grass production was approximately 6.5. The P uptake was significantly higher in the treated biochar pots, both after high and low pH treatment. The more extreme pH treatments gave the highest uptake. The DGT uptake gave the same broad picture for pots with biochar but not for pots with sludge. DGT uptake showed less diffenece between high and low pH treatments. The passive samplers correlated relatively well with the measured grass uptake.

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Municipal solid waste landfills are expected to be potentially important sources of gaseous mercury (Hg)(Lindberg et al. 2005). Such emissions can be difficult to locate and measure, since landfills can have diffuse, non-point emissions and the gas can also escape horizontally over large distances in unsaturated layers. The primary objective in this work was to investigate the possibility of depletion of gaseous mercury by means of moss transplants. The investigation was carried out at Solgård waste disposal site, an active landfill since its start-up in 1978, located in Moss, Norway. Today the landfill is licensed as a landfill for ordinary waste. The area of the landfill is estimated to be about 204 000 m2. Goodman and Roberts (1971) first introduced the “moss bag” technique, which was later modified by Little and Martin (1974). Hylocomium splendens, known for its capability as bio monitor since 1968 (Ruhling & Tyler 1968), was collected from an uncontaminated site, dried at room temperature and loaded in fine meshed nylon nets. Moss bags were made up of a frame of 10 x 10 cm square of thin wood sticks, filled with 1 gram of moss finely distributed and covered up by the nets. The moss bags were placed in two heights, about 40 and 100 cm above ground. A total of 130 moss bags were placed at suitable locations covering the landfill surface, with special attention to such places as gas vents and locations with suspicious odours. For comparison, moss bags were also placed a couple of kilometres north, south, west and east of the landfill. The exposure time was 6 months, lasting from primo October 2013 until the end of March 2014. About 0.2 g samples of air dried moss were subjected to acid digestion in a closed microwave system (260 0C) prior to analysis with inductively coupled plasma mass spectrometry, using an Agilent 8800 QQQ instrument. Results from ongoing work will be presented. References Goodman, G. T. & Roberts, T. M. (1971). Plants and soils as indicators of metals in the air. Nature, 231 (5301): 287-292. Lindberg, S., Southworth, G., Prestbo, E., Wallschläger, D., Bogle, M. & Price, J. (2005). Gaseous methyl-and inorganic mercury in landfill gas from landfills in Florida, Minnesota, Delaware, and California. Atmospheric Environment, 39 (2): 249-258. Little, P. & Martin, M. H. (1974). Biological Monitoring of Heavy metal pollution. Environmental Pollution, 6: 1-19. Ruhling, A., & Tyler, G. (1968). An ecological approach to lead problem. Botaniska Notiser, 121(3), 21.

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Large quantities of mercury (Hg) containing waste have been deposited on MSW landfills for half a century. Despite its known volatility, persistence, and toxicity in the environment, the fate of Hg in landfills has not been widely studied. However, the generation of methane by anaerobic bacteria suggests that landfills may act as bioreactors for methylated mercury (Me-Hg) (Lindberg et al. 2005). Studies conducted at operating landfills in the US identified and quantified both gaseous inorganic and Me-Hg species. Lindberg and co-workers (2005) estimated an average atmospheric Hg release in landfill gas (LFG) of about 300-400 mg/d, where the methylated forms of Hg were calculated to be 1- 10 mg/d. Industrial and commercial uses of Hg are regulated in many countries. The Norwegian government has introduced several resolutions with the intention to halting the Hg emissions by 2020 (Miljødirektoratet 2013). In an investigation by Øygard et al. (2004) it was found that less than 0.02% of the Hg deposited in a MSW landfill was discharged through the leachate, even without leachate treatment plants. Data on whether gas discharged from Norwegian MSW landfill sites contains any form of Hg are missing. As restrictions against the use of Hg in a number of products are adopted, most recently in 2008 (Miljødirektoratet 2013), there is every reason to believe that there are traces of Hg in discharged landfill gas. Discharged gas is sampled at Solgård waste disposal site in Moss, Norway, an active landfill established in 1978. Currently the landfill covers a surface area of approximately 204 000 m2. Different forms of mercury in LFG are sampled by means of a three pieces cassette packed with three selective adsorbents. In the first piece, an untreated cellulose support pad is used for trapping particles. For the determination of inorganic mercury (Hg0), cellulose support pads impregnated with palladium (Pd) is placed in the second piece. The last piece is filled with a CarbopackTM adsorbent for determination of organic Hg. The flow rate is set to 3 L/min for 3 hours. Subsequently, the adsorbents are subjected to acid digestion in a closed microwave system (260 0C) prior to analysis with ICP-MS. Use of CarbopackTM also allow us to simultaneously determine tin (Sn). Organic Sn is, like organic Hg, of interest in terms of hazardous pollutants, although it is not yet adopted restrictions for its use. Results from ongoing field and laboratory work will be presented. References Lindberg, S., Southworth, G., Prestbo, E., Wallschläger, D., Bogle, M. & Price, J. (2005). Gaseous methyl-and inorganic mercury in landfill gas from landfills in Florida, Minnesota, Delaware, and California. Atmospheric Environment, 39 (2): 249-258. Miljødirektoratet. (2013). Miljøstatus: Kvikksølv. Available at: http://www.miljostatus.no/Tema/Kjemikalier/Noen-farlige-kjemikalier/Kvikksolv/ (accessed: 09.01.2014). Øygard, J. K., Måge, A. & Gjengedal, E. (2004). Estimation of the mass-balance of selected metals in four sanitary landfills in Western Norway, with emphasis on the heavy metal content of the deposited waste and the leachate. Water research, 38 (12): 2851-2858.

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Det er tatt prøver av jord rundt AF Decoms anlegg ved Raunes fiskefarm i Vats. Prøvetakingen er uført i to omganger, i mai og juli 2014. Det er tatt totalt 40 prøver i topplaget og 32 prøver på ca. 20 cm dyp. PCB og bisfenol A ble ikke påvist i noen av prøvene. Spesifikk radioaktivitet varierte mellom 0.27 til 0.57. Grenseverdier for tilstandsklasse ”meget god” ble overskredet for kvikksølv (Hg) og sink (Zn). Størst forskjell i fordelingen av konsentrasjoner i øverste jordlag og i dyp 20 cm vises for Hg, As og til dels Zn. Denne forskjellen i mønster kan tyde på en annen kilde for konsentrasjonene av Hg, As og Zn, trolig påvirket av nedfall fra luft, i forhold til de øvrige tungmetallene. Mye av eventuelle utslipp er trolig vasket ut som overflateavrenning.

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SUMMARY: With new legislation regarding the waste sector we have studied changes in the average compostion of leachate from municipal solid waste (MSW) landfills from 1998 to 2002, compared to 2005 to 2010, based on standard monitoring programmes from six landfiills. As expected the concentrations of BOD and phosphorous have been reduced in the studied period, but not COD. Nitrogen and sulphur seem to have increased. As intended also Cd, Cr and Hg whereas Pb seems to have been increased. Also salt elements, such as Na and K, increased. Most organic parameters are reduced except for oil and pesticides. The treatment at the six locations seems to be as effective as expected

Sammendrag

Tracers can be used to monitor emisions of leachate from landfills, in order to detect hydrological pathways and to evaluate environmental pollution. We investigated the occurrence of the stable carbon isotope ratio (13C measured in dissolved inorganic carbon, or d13C-SCO2) and tritium (3H), in addition to parameters commonly found in relatively high concentrations in leachate such as chloride (Cl), organic matter (COD), nitrogen (Total and NH4-N), iron (Fe), electrical conductivity and pH. The sampling was performed at seven landfills in the south-eastern part of Norway during a period of 5 years. The objective was to evaluate the potential for tracing leachate in the environment with emphasis on groundwater pollution.  By analyzing the d13C-SCO2 ratio in leachates, ground waters and surface waters the influence of leachate can be identified. The content of d13C-SCO2 varied from -5.5 to 25.9‰ in leachate, from -25.4 to 14.7‰ in groundwater, and varied between -19.7 to -13.1‰ in creeks. A comparison of the content of carbon isotope ratio with the concentrations of the compounds COD, electrical conductivity, Total- and NH4-N, Cl and Fe showed that d13C-SCO2 is a good tracer for leachate due to higher sensitivity compared to other parameters. The mean concentration of all the studied parameters was higher in the leachate samples, however, only the carbon isotope ratio showed significant differences between all of the groups strongly and weakly polluted and unpolluted samples, showing  that it can be used as a practical tracer for lechate in groundwater and surface water. The carbon isotope ratioshowed strong correlation between nitrogen and electrical conductivity, and bicarbonate, but not with pH. Tritium was only found sporadically in low concentrations and is considered not suitable as a tracer at the sampled locations.

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A literature review shows that more than 500 organic and metallic compounds have been reported occurring in wetlands, and also that wetlands are suitable for removing pollutants. There are, however, obvious pitfalls for treatment wetlands, the most important being the maintenance of the hydraulic capacity and controlling the detention time. Treatment wetlands should have an adapted design to target specific compounds. Aquatic plants and soils are suitable for wastewater treatment because they have a high capacity of removing nutrients and other substances through uptake, sorption and microbiological degradation. The heavy metals Cd, Cu, Fe, Ni and Pb were found to exceed limit values in water. Also these studies revealed high values of phenol and SO4. No samples showed concentrations in sediments exceeding limit values, but fish samples showed concentrations of Hg exceeding the limit for fish sold in the EU. The main route of heavy metal uptake in aquatic plants was through the roots in the case of emergent and surface floating plants, whereas in submerged plants roots as well as leaves take part in removing heavy metals and nutrients. Submerged rooted plants have potential from water as well as sediments, where as rootless plants extracted metals rapidly only from water. Caution is due about the use of SSF CWs for the treatment of metal-contaminated industrial wastewater as metals are shifted to another environmental compartment and moreover stable redox conditions are required to ensure long-term efficiency. Mercury is one of the most toxic heavy metals and since wetlands have been shown to be a source of methylmercury. Methyl Hg concentrations are typically approximately 15% of Hgt. In wetland water samples, PAH, bisphenol A, BTEX, hydrocarbons including diesel range organics, glycol, DDT, PCB, cyanide, benzene, chlorophenols and formaldehyde were found to exceed limit values. In sediments only PAH and PCB were found exceeding limit values. In the water phase the pesticides found above limit values were atrazine, simazine, terbutylazine, metolachlor, mecoprop, endosulfan, chlorfenvinphos and diuron. There are few listings of these compounds in the commonly used water quality limit values, except for some well-known endocrine disrupters such as nonylphenol, phtalates etc. The performance of extensive household wastewater treatment systems of removing pharmaceuticals and personal care products (PPCPs) are similar to that obtained in conventional activated sludge wastewater treatment plants

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A research has been undertaken studying pesticide residues in water from greenhouses and the use of soils and filter materials to reduce such losses. The pesticides detected in water samples collected downstream greenhouses include 9 fungicides, 5 herbicides and 4 insecticides. 10 compounds from flower and vegetable productions were frequently found to exceed environmental risk levels, and with a few exceptions the compounds were found in higher concentrations than those typically found in agricultural runoff. Some compounds were found in high concentrations (.1mg/l) in undiluted runoff from greenhouses producing vegetables. Nutrient concentrations in the runoff were also sporadically very high, with phosphorous values varying between 0.85 and 7.4mgP/l, and nitrogen values between 7.5 and 41.4mgN/l. Undiluted runoff from the productions showed values of 60mgP/l and 300mgN/l. High values of pesticides correlated with high values of nutrients, especially P. Column experiments using a sandy agricultural soil and stock solutions of non-polar and slightly polar pesticides mixed with a complex binder and nutrients showed a significant reduction for nearly all of the compounds used, indicating that transport through soil will reduce the concentrations of the studied pesticides. The pesticide adsorption capacity of the filter materials pine bark, peat, Sphagnum moss, compost, oat straw, ferrous sand and clay soil were tested in batch and column experiments. Adsorption were studied contacting the filter materials with aqueous solutions containing greenhouse production pesticides. The batch experiments showed that pine bark and peat, both combining a high content of organic matter with a low ph, provided the highest adsorption for most of the tested pesticides. Sphagnum moss, compost and oat straw also showed high adsorption for most of the pesticides, while the mineral filters provided the lowest adsorption (30-55%). Further column experiments confirmed these results, displaying the best removal efficiency in the organic materials, varying from 200mg/g in compost, to 500mg/g in moss, straw and pine bark.

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Sigevann ved Teigen er analysert i alt 6 ganger i 2008, ved tidsproporsjonale blandprøver og stikkprøver. Det er tatt prøver av råvann og ut våtmark, samt sedimentprøve i sigevannet. I tillegg er det tatt prøver fra bekk oppstrøms og nedstrøms anlegget, samt i nærliggende grunnvannsbrønn. Målt sigevannsproduksjon i 2008 var ca. 32 000 m3, eller 87 m3/dag. Sigevannsanlegget har i gjennomsnitt oppnådd følgende rensegrader: 42 % for KOF, 83 % for Tot-N og 90 % for Tot-Fe. Rensingen av KOF er lavere enn kravet. Innholdet av organiske miljøgifter og tungmetaller er lavt i renset sigevann, med unntak av Ni og enkelte plantevernmidler. Det er forhøyde konsentrasjoner av jern og nitrogen nedstrøms deponiet i resipienten. Enkelte plantevernmidler er også påvist i bekken. Fosfor er blitt tilsatt lufteanlegget i vekstsesongen, noe som ser ut til å ha bedret fjerningen av nitrogen. Det anbefales at tilsetningen av fosfor fortsetter i vekstsesongen 2008.

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The use of pesticides is a potential threat to local groundwater. Once groundwater is contaminated, it is very difficult to clean.Thus, it is of importance to assess the risk of contaminating local groundwater at an early stage when pesticides are found in soils. This knowledge will also help in remediation strategies. Traditional methods of deterministic analysis cannot explicitly account for the sometimes large uncertainties that exist at this stage in the work,  whereas probabilistic analyses are better suited for dealing with these problems. In this paper, we have combined contaminant transport with a 1st-order reliability approach. Pesticide concentrations in soil have been studied to estimate the probability of failure—that is, of pesticides exceeding established critical levels in groundwater. Results indict that failure probability increases rapidly with in a certain range of pesticide concentrations in soil for different critical levels. In given aquifer conditions and contaminants, probabilities of contaminants exceeding particular critical levels can easily be obtained according to various water usage scenarios. The distribution of importance factors among variables indicates the contribution their relative weights make to the failure probability. Hence, authorities can easily form sensitivity factors to take action and reduce the risk of contaminating the groundwater.

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SUMMARY: Tracers should be used to monitor emissions of leachate from landfills, in order to evaluate environmental pollution. We investigated a selection of parameters commonly found in leachate, in addition to isotopic and radioactive tracers, and their efficiency in tracing leachate in the environment, with emphasis on groundwater. A study at 6 landfills focused on the occurrence of the isotopes 13C and 3H in leachate, surface and groundwater, in relation to the water balance at the sites. The content of heavy carbon (δ13C) in leachate varied between 5.5 to 25.5, in groundwater it reached 4.7 when polluted, and varied between -11.8 to -24.2 when unpolluted, and in surface water from -13.1 to -19.7. Measurements of tritium did not show any systematic trend in the leachate and groundwater samples. Also the elements Fe, B and Cr, and to a minor degree Mn and Zn, showed higher contrasts in leachate/groundwater concentrations. A comparison of the concentrations of tracer compounds with detailed estimation of the water balance at 3 landfills showed that 13C seems to be the most reliable tracer and the factor correlating best with estimates of diffuse losses of leachate to groundwater.

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Det ble i 2007 gjennomført prøvetaking av grunnvannsbrønner i 9 områder i Norge, med det formål å kartlegge forekomst av pesticider i viktige norske grunnvannsforekomster i tilknytning til jordbruksarealer. I hvert område ble 3-8 brønner prøvetatt, hvilket ga 46 brønner totalt. Det ble tilstrebet å gjennomføre prøvetaking i områder i tilknytning til viktige grunnvannsressurser og med en viss jordbruksintensitet. Det var også fokus på å velge ut områder med ulike typer drift for å få et inntrykk av hvilken risiko ulike driftsformer representerer. Følgende områder ble valgt ut for prøvetaking: Klepp i Rogaland, Lærdal i Sogn og Fjordane, Kongsberg i Buskerud, Øyer i Gudbrandsdalen (Oppland), Grue i Solør (Hedmark), Ullensaker og Nannestad i Akershus, Rena i Østerdalen (Hedmark), Melhus i Sør-Trøndelag, og Stjørdal og Meråker i Nord-Trøndelag. Det ble i første rekke tatt prøver av eksisterende drikkevannsbrønner (fortrinnsvis private gårdsbrønner). Det ble i hovedsak analysert for pesticider (sprøytemidler), nitrat og ammonium. […]

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It is generally recommended that solutions for the treatment of wastewater and toilet waste is based on a detailed knowledge of the local physical and natural conditions as well as socio-economical factors and socio-cultural factors. Based on experience from previous comparable projects the following components are recommended: " The systems should be build as large as possible based on local natural/financial resources " Infiltration systems are preferred if local soil is usable and local water resources are protected " A combination with pre-treatment, compact filtering and extensive filtering in wetlands or peat filters Based on experience from previous comparable projects the following components might also be recommended given a local acceptance: " Urine separating toilets without water/low water consumption " Separate collection of urine in tanks to be stored and reused or safely disposed off " Toilet solid waste to be stored in separate tanks and co-treated with other organic waste fractions " Separate treatment of greywater and urine in extensive infiltration or filter systems These systems makes it possible to a safe, odour free and recycling waste and wastewater treatment without creating unacceptable loads on the environment or risks to human health. Infiltration systems depend on local soils and previous use of ground water.

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EU-legislation, in particular the Landfill Directive, requires environmental monitoring of landfills, both pre- and post closure. The content of the guidelines of the Nordic countries that are brought together in this report are based on the requirements given in European legislation. Thus, the guidelines in this report are relevant for landfills subject to EU legislation.

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Program for Jord- og vannovervåking i landbruket (JOVA) ledes av Bioforsk Jord og miljø, og utføres i samarbeid med en rekke andre institusjoner. Programmet rapporterer årlig overvåkingsresultater fra jordbruksdominerte nedbørfelt over hele landet. Feltene representerer ulike driftsformer, jordbunnsforhold, og hydrologiske og klimatiske forhold. De årlige feltrapportene beskriver jordbruksdrift, og avrenning og tap av næringsstoffer og partikler i de ulike feltene. Tap av partikler og næringsstoffer rapporteres for agrohydrologisk år, 1. mai - 30. april, mens tap av pesticider rapporteres for kalenderår.

Sammendrag

Sigevann ved Teigen er analysert i alt 6 ganger i 2006, ved tidsproporsjonale blandprøver, samt stikkprøver med utvidet program. Det er tatt prøver av råvann, ut lagune og ut biodam. I tillegg er det tatt prøver fra bekk oppstrøms og nedstrøms anlegget, samt i nærliggende grunnvannsbrønn. Målt sigevannsproduksjon i 2006 var ca. 29 000 m3, eller 57 m3/dag, 25 % høyere enn normalt. Sigevannsanlegget har i gjennomsnitt oppnådd følgende rensegrader: 32 % for KOF, 40 % for Tot-N og 71 % for Tot-Fe. Rensingen er bedre enn i 2005. Rensingen av KOF er lavere enn kravet. Innholdet av organiske miljøgifter og tungmetaller er lavt i renset sigevann, med unntak av en del tungmetaller og ugrasmidler. Det er påvist ugrasmidler i grunnvannet i lave konsentrasjoner nedstrøms. Det er forhøyde konsentrasjoner av jern og nitrogen nedstrøms. Pesticider er også påvist i bekken. Det anbefales at tilsetningen av fosfor fortsetter i vekstsesongen 2007.

Sammendrag

Agricultural runoff contributes with significant amounts of nitrogen (N) to rivers and lakes causing water quality problems. Constructed wetlands (CWs) in first- and second order streams reduce downstream loading of nutrients through mechanisms such as sedimentation, uptake by vegetation and microbial denitrification. (A stream with no tributaries (headwater stream) is considered a first order stream. A segment downstream of the confluence of two first order streams is a second order stream [1]). Norwegian CWs are often too small to easily achieve high N-retention. It is therefore important to improve and optimize the N-retention processes in the CWs where the CW area cannot be increased due to local restrictions. The main aim of this project was to compare N-retention in an experimental wetland including eight different types of organic and mineral CW-filters, one of which was a standard Norwegian CW (depth 0.5 m). The average total-N retention through the experimental wetland was 17 % for the period of May-September in 2003, but only 2% in the same period in 2004. Converted to mass, the retention in 2003 was 168 kg and 26 kg in 2004. Lower retention in 2004 was probably mainly caused by higher hydraulic load that year. The organic filters performed better than the mineral filters and the standard CW.

Sammendrag

Sigevannet ved Oksrud og Paddetjern er overvåket ved å ta stikkprøver nedstrøms deponiene. Utslippsmengder er anslått med bakgrunn i vurderinger av gjennomsnittsverdier for avrenningen. Det er særlig fenoler, PAH, Fe, Cd og Zn som øker tildels kraftig nedstrøms deponiet ved Paddetjern. Det er tildels høye konsentrasjoner av tungmetallene Zn, Ni og Cd i kilden ved deponiet Oksrud. Det er en klar forbedring av vannkvaliteten ved kilden lenger nedstrøms, men konsentrasjonen både av Zn og særlig Cd er fortsatt høy. De foreslåtte tiltak ved lokalitetene anbefales gjennomført i 2007

Sammendrag

Sigevannet ved Esval ble i 2006 overvåket ved å ta blandprøver før og etter rensing, samt stikkprøver for utvidet analyseprogram. Rensingen av sigevann fra Esval har vært svært god i 2006, med rensegrad for alle konsesjonsparametrene >99%. Basert på totalavrenningen utgjør utslippet med sigevann om lag 1753 kg KOF, 701 kg NH4-N

Sammendrag

Sigevannet ved HRA ble i 2006 overvåket ved å ta stikkprøver før og etter rensing. Renseanlegget omfatter luftet lagune og sedimentering. I tillegg ble det tatt prøver av grunnvannet i 4 brønner. Brønn B6 nedstrøms er blitt ødelagt pga. isspregning. Rensingen av sigevann har vært god i 2006, med følgende rensegrader; 93 % for KOF, 50 % for Tot-N, 70 % for NH4-N og 95 % for Fe, til tross for en tilsynelatende betydelig økning i konsentrasjonene. Basert på totalavrenningen utgjør utslippet med sigevann om lag 80 t KOF, 4 t Tot-N og 700 kg Fe. Organiske miljøgifter analysert i 2006 omfatter fenoler, metylfenoler, klorfenoler og BTEX. Innholdet i renset sigevann er lavt. Sigevannet som slippes ut til infiltrering i grunnvann, har høye nivåer av N, Fe, Mn, Cu, Cr og Ni. Grunnvannet under deponiet har forhøyde nivåer av Mn, Cu.

Til dokument

Sammendrag

Pesticide losses to the environment are unwanted due to possible environmental and health hazards. An experimental wetland is established to study the efficiency with respect to retention of sediments, nutrients and pesticides. Pesticides were applied on an arable soil plot in the watershed. Statistical analyses were carried out on three selected pesticides; propachlor, metalaxyl and chlorfenvinfoss. All pesticides were found in the experimental wetland, with peak concenttrations shortly after spraying. In 2003 pesticide retention varied from 11% to 42% and in 2004 retention varied from 19% to 56 %. Comparing eight different wetland filters, we found that L6 and L8, with flagstones and straw, respectively, had a higher total pesticide retention than a standard Norwegian wetland (L4). When the compounds were treated separately, however, the picture was different. Statistical analyses showed that the treatments were signficantly different from zero in six of the wetlands for remowal of propachlor, for removal of metalaxyl none were significantly different, and for removal of chlorfenvinphos four treatments were significantly different. For the three compounds none of the relative treatments were significantly different from L4. Chemical properties of the pesticides could explain some of the behaviour in the watershed and in the wetland.

Sammendrag

Pesticides in Norwegian ground water have been monitored since 1995. Here we report data including 2004. The monitoring has focused on shallow groundwater near agricultural fields (4 locations), farm wells (22 locations) and on public water works (38 locations), 450 samples were analyzed for a total of 62 pesticide compounds and metabolites, and the result was 514 detections of single compounds. Altogether 27 pesticides and metabolites were detected; 2 insecticides, 9 fungicides and 16 herbicides. Herbicides were most frequently detected (in 79% of the samples), followed by fungicides (20%) and insecticides (1%). Pesticide concentration was generally low, although high concentrations also occurred, for example 33 "g/l of metribuzine in shallow ground water near agricultural fields, and 20 "g/l of bentazon in a farm well. Some water soluble pesticides occurred both frequently and with relatively high concentrations in shallow ground water near agricultural fields. The results show that local ground water near farms is vulnerable for contamination of pesticides and needs further monitoring. Efforts should be made to minimize contamination of wells in farming areas through education on pesticide use, monitoring and well positioning. Few pesticides were detected in ground water from water works and the concentrations were low. Monitoring of water works ended in 2002. The data show that there is a continuous need to monitor pesticides as well as selected metabolites in shallow ground water and wells near agricultural fields in Norway.

Sammendrag

Bioforsk jord og miljø avslutter nå et strategisk program Binding og mobilisering av organiske miljøproblemstoffer som har pågått siden 2001. Det første året ble det tatt sigevannsprøver fra en kommunal fylling. Ved en fullscreening-analyse ble det påvist stoffer som en tradisjonelt ikke har tenkt på som miljøproblem-legemidler og luktstoffer brukt i mange personlige hygiene- og husholdningsprodukter

Sammendrag

Program for Jord- og vannovervåking i landbruket (JOVA) ledes av Bioforsk Jord og miljø, og utføres i samarbeid med en rekke andre institusjoner. Programmet rapporterer årlig overvåkingsresultater fra nedbørfelt over hele landet. Feltene representerer ulike driftsformer, jordbunnsforhold, og hydrologiske og klimatiske forhold. De årlige feltrapportene beskriver jordbruksdrift, og avrenning og tap av næringsstoffer og partikler i de ulike feltene. Tap av partikler og næringsstoffer rapporteres for agrohydrologisk år, 1. mai - 30. april, mens tap av pesticider rapporteres for kalenderår.

Sammendrag

Overvåking av forekomst av pesticider i grunnvann i jordbruksområder inngår som en del av programmet Jord- og vannovervåking i landbruket (JOVA). Overvåkingen av overflatenært grunnvann har pågått siden 1995, mens overvåkingen av drikkevannsbrønner startet i 1998. I 2005 ble overflatenært grunnvann overvåket ved to lokaliteter, Vasshaglona i Grimstad og Heiabekken i Råde (totalt 5 brønner). Også 4 drikkevannsbrønner lokalisert utenfor JOVA-felt ble prøvetatt. Totalt i perioden 1997-2005 er det tatt prøver i 22 drikkevannsbrønner. Det ble påvist pesticider i alle brønnene som ble prøvetatt for overflatenært grunnvann i 2005. To av brønnene viser en signifikant nedgang i total konsentrasjon av pesticider gjennom overvåkingsperioden. Det ble påvist pesticider i 3 av de 4 drikkevannsbrønnene som ble prøvetatt. To av disse viser en tendens til økt total konsentrasjon av pesticider gjennom overvåkingsperioden, men økningen er ikke signifikant.

Sammendrag

Sigevann ved Teigen er analysert i alt 6 ganger i 2005, ved tidsproporsjonale blandprøver, samt stikkprøver med utvidet program. Det er tatt prøver av råvann, ut lagune og ut biodam. I tillegg er det tatt prøver fra bekk oppstrøms og nedstrøms anlegget, samt i nærliggende grunnvannsbrønn. Målt sigevannsproduksjon i 2005 var ca. 13 900 m3, eller 38 m3/dag. Sigevannsanlegget har i gjennomsnitt oppnådd følgende rensegrader: 25 % for KOF, 38 % for NH4-N og 94 % for Tot-Fe. Rensingen av KOF er lavere enn det som vanligvis blir stilt krav om. Bekken er også prøvetatt før og etter utslipp og viser ingen tegn til økning i uønskede stoffer. Pesticider er også påvist i bekken. Det er gitt forslag til analyseprogram for 2006.

Sammendrag

Sigevann fra deponi med bunntetting, samt fra behandlingsanlegg for organisk avfall, samles opp og forbehandles i et lufte- og sedimenteringsanlegg. Etter forbehandling skal sigevannet infiltreres i grunnen. Det er gjennomført feltundersøkelser med formål og foreslå nytt anlegg for infiltrasjon og overvåking av sigevannet transport til og i grunnvannet. Strømningsforholdene under eksisterende infiltrasjonskummer samt lagdeling i løsmassene er kartlagt med geofysiske metoder. Forslag til nytt infiltrasjonsanlegg samt fremtidig overvåking er gitt. Anlegget foreslås som et todelt infiltrasjonsbasseng i grop ved siden av eksisterende behandlingsanlegg.

Sammendrag

The concentrations of carbon monoxide (CO) and other gases were measured in the emissions from solid waste degradation under aerobic and anaerobic conditions during laboratory and field investigations. The emissions were measured as room temperature headspace gas concentrations in reactors of 1, 30, and 150 L, as well as sucked gas concentrations from windrow composting piles and a biocell, under field conditions. The aerobic composting laboratory experiments consisted of treatments with and without lime. The CO concentrations measured during anaerobic conditions varied from 0 to 3000 ppm, the average being 23 ppm, increasing to 133 ppm when methane (CH4) concentrations were low. The mean/maximum CO concentrations during the aerobic degradation in the 2-L reactor were 101/194 ppm without lime, 486/2022 ppm with lime, and 275/980 ppm in the 150-L reactors. The presence of CO during the aerobic composting followed a rapid decline in O2 concentrations Significantly higher CO concentrations were obtained when the aerobic degradation was amended with lime, probably because of a more extreme depletion of oxygen. The mean/maximum CO concentrations under field conditions during aerobic composting were 95/1000 ppm. The CO concentrations from the anaerobic biocell varied from 20 to 160 ppm. The hydrogen sulfide concentrations reached almost 1200 ppm during the anaerobic degradation and 67 ppm during the composting experiments. There is a positive correlation between the CO and hydrogen sulfide concentrations measured during the anaerobic degradation experiments.

Sammendrag

Sigevannet ved Esval ble i 2005 overvåket ved å ta blandprøver før og etter rensing, samt stikkprøver for utvidet analyseprogram. Rapporten omfatter også resultatene av en undersøkelse av lekkasje fra dreneringen, samt stikkprøve tatt i februar 2006 for vurdering av renseanlegget. Rensingen av sigevann fra Esval har vært svært god i 2005, med rensegrad for alle konsesjonsparametrene >99%. Basert på totalavrenningen utgjør utslippet med sigevann om lag 263 kg KOF, 316 kg NH4-N og 4,6 kg Fe. Analyser av miljøgifter i 2005 omfatter tungemetaller og organiske miljøgifter som fenoler, metylfenoler, alkylfenoler og -etoksilater, tinnorganiske forbindelser og BTEX. Innholdet av miljøgifter i renset sigevann er lavt.

Sammendrag

Sigevannet ved HRA ble i 2005 overvåket ved å ta stikkprøver før og etter rensing. I tillegg ble det tatt prøver av grunnvannet i 4 brønner. Rensingen av sigevann har vært moderat i 2005, med følgende rensegrader for de ulike konsesjonsparametrene; 51 for KOF, 45 for Tot-N, 64 % for NH4-N og 57 % for Fe. Basert på totalavrenningen utgjør utslippet med sigevann om lag 10,2 t KOF, 7,4 t Tot-N og 100 kg Fe. Organiske miljøgifter analysert i 2005 omfatter fenoler, metylfenoler, klorfenoler og BTEX. Innholdet i renset sigevann er lavt.

Sammendrag

Bioforsk Jord og miljø har utarbeidet detaljplan for behandling av sigevann fra Paddetjern deponi i et naturbasert renseanlegg. Bioforsk Jord og miljø søker på vegne av Ski kommune teknisk etat, om etablering av renseanlegg for sigevann fra Paddetjern deponi, Siggerud. Nedbørfeltet er på 92 da hvorav 20 da er deponiareal og ca 40 da drenerer via en myr nord for deponiet. Dimensjonerende vannmengde er i gjennomsnitt på 5 m3/time. Dimensjonerende renseareal for denne typen anlegg bør være på minimum en ukes oppholdstid. Arealet som er prosjektert gir ca 12 dagers oppholdstid i gjennomsnitt. Anlegget består av et sedimentasjonsbasseng (800 m2, 2 meters dyp) med styrt strømning, ettterfulgt av et grunnere basseng (650 m2, 1 meters dyp) med torvfilter og tilplanting. Hvis overvåkningen krever at renseevnen optimaliseres kan lufting ettermonteres i innløpsdelen av sedimentasjonsbassenget, flere filterløsninger monteres i bassenget og / eller etterpolering anlegges i lokalt myrområde nedstrøms renseanlegget.

Sammendrag

Sigevann fra de nedlagte deponiene Paddetjern og Oksrud medfører uønskede utslipp. En analyse av mulige tiltak viser at et renseanlegg bestående av lufting og muligens også filtrering av sigevannet vil kunne gi tilfredsstillende rensing over tid med et effektivt kost/nytte-forhold ved Paddetjern. Ved Oksrud anbefales fortsatt rensing i stedlige sandmasser. Kartleggingen av lokalitetene har vist at det er tilgjengelige arealer til rensing. Begge lokalitetene bør følges opp med overvåking av sigevannet.

Sammendrag

Several biocells varying from 100 m3 to about 8000 tons have been established at waste treatment locations in Norway since 1998. We studied biocells by characterizing the waste material by degradation, gas and leachate emission and post-treatment potential, by taking several samples distributed in space and time. Field sample analyses were water content, leachate temperature, redox conditions, oxygen content, electrical conductivity and pH, and gas temperature, O2, CH4 and CO2 concentrations. Waste samples were drilled up by a 10-inch auger down to 6 m depth. The collected samples were analyzed and used for composting experiments. The temperature in the biocelles varied between 10 to 14 ºC in the period from august to December. The waste was characterised as completely or slightly completely degraded after 4 years of biocell storage/treatment, based on "Rotte-test" and respirometer analyses. Microbial analyses showed that the material was free from salmonella, but contained some thermotolerant colibacteria in the most degraded part. Samples from the slightly degraded waste were also free from thermotolerant colibacteria. None of the waste samples showed any inhibition against the germination of plants. The temperature in the most degraded material did not increase significantly during composting. This material can thus not be treated aerobically after removal from the biocell, ie. for reducing pathogens. The factors leachate strenght measured as electrical conductivity, BOD and C/N-ratio best explained the methane content of the biogas in each sampling point. A total production of 593 t landfill gas has been measured from the large biocell. The annual mean methane concentration increased from 28 to 56%, with an overall mean of 48%. This gives a 21% degradation of organic carbon in four years, based on certain assumptions on the incoming waste. The estimated degradation of organic matter is between 50% and 75% in four years.

Sammendrag

Hydrogen sulphide (H2S) is known to be a major odourant in landfills. We have studied H2S production from landfill residual waste with and without added sulphur as waste from plasterboards. We also studied the influence of water content in the waste. The lab experiments were conducted in 30-l plastic containers with controlled water level. We also studied the effectiveness of different reactive layers to remove H2S. The organic waste produced H2S in the order of 40 ppm over a period of 80 days. When plasterboard was added, the H2S production with a high water level increased to 800 ppm after a lag period of about 40 days, and to about 100 ppm after 50 days with low water content. The CH4 concentration in the initial experiment increased to 55% to 70% after 80 days. The CH4 concentration in the second experiment increased to nearly 70% in the container with high water content, slowly declining to nearly 60% between 20 and 60 days. In the container with low water content the CH4 concentration increased to 60% and stayed nearly constant. In the container with high water level a decline in the CH4 concentration was observed coinciding with a presence of CO. The results from the experiments with reactive layers were not available before submitting the proceeding.

Sammendrag

Summary: This experiment simulate aerobic treatment to see if the field removal rates can be duplicated in the laboratory, and also to see if there are some physical or chemical factors that significantly influence this removal. The experiment used 3 leachates and 8 artificial samples with varying concentrations of Cl, TOC, Tot-N and Fe, and 4 controls. Leachate samples were collected from Dal Skog and Esval landfills. Some of the samples were centrifuged after respiration.The oxygen consumption in the leachate samples was considerably lower than in the artificial samples, probably due to inhibitory compounds in the leachate. Mean Cl removal was 21.6% for the leachate samples, 46.0% in the artificial samples and 9.97% in the controls. Only TOC showed significant influence on the oxygen consumption in the respirometer, both when measured in the artificial samples (p< 0.036) and for all samples (p

Sammendrag

På jordbruksarealer i nedbørfeltet til Heiabekken, Østfold og Vasshaglona Aust-Agder er overflatenært grunnvann undersøkt for plantevernmidler. I Østfold, Vestfold og Akershus er 19 drikkevannsbrønner i jordbruksområder er undersøkt. Data om bruken av plantevernmidler i nærområdet til brønnene er samlet inn. Det ble i 1998 påvist til sammen syv ulike plantevernmidler i overflatenært grunnvann på jordbruksarealer: bentazon, metalaksyl, metribuzin, metamitron, MCPA, propaklor og dikloroprop. Høyeste konsentrasjon av ett enkeltstoff var 3.0 ?g/L metribuzin i prøve tatt 20 juli. Høyeste sumkonsentrasjon av plantevernmidler var 4,71 ?g/L. Det ble i 1998 og 1997 påvist i alt ti ulike plantevernmidler i konsentrasjoner fra 0.01 – 1.0 ?g/L i gårdsbrønner i jordbruksområder. Av 77 vannprøver inneholdt 37 prøver positive funn. Av 19 gårdsbrønner inneholdt 10 brønner plantevernmidler. I alt 14 prøver hadde konsentrasjon over anbefalt grense for drikkevann til vannverk (0.1 ?g/L for enkeltstoffer). Det ser ikke ut til å være noen entydig sammenheng mellom brønndyp og forekomst av plantevernmidler. Resultatene viser at for drikkevannsbrønner i jordbruksområder er det en risiko for å finne rester av plantevernmidler.

Sammendrag

Erosjon og næringsstofftap overvåkes i en rekke mindre nedbørfelter som representerer ulik jordbruksdrift, klima og jordsmonn i Norge. Overvåkingsprogammet ble satt i gang 1992, men en del av nedbørfeltene har målinger fra midten av 80-tallet. Erosjon og næringsstofftap er beregnet for agrohydrologiske år, 1. mai 1999– 30. april 2000. Året 1999/2000 var preget av generelt høye nitrogentap i Grimestadbekken, Vasshaglona og Hotrankanalen (10-12 kg N/dekar), mens det for de øvrige feltene var mindre enn 5 kg N/dekar. I kornfeltene på Østlandet var nitrogentapet 2-5 kg/dekar, som er på nivå med middeltapene for hele måleperioden. I nedbørfelt med overveiende grasdyrking varierte nitrogentapene fra 1-5 kg/dekar, størst i nedbørfelt med størst husdyrtetthet. Svært store fosfortap ble registrert i Grimestadbekken (1220 g/dekar) og Vasshaglona (720 g/dekar) i 1999/00. I Hotrankanalen var fosfortapet 430 g/dekar. I kornfeltene i Akershus varierte fosfortapet 120-340 g/dekar, mens det på Hedmarken var 40 g/dekar. I nedbørfelter med overveiende grasdyrking ble det registret fosfortap på 30-500 g/dekar i 1999/00. Nedbørfeltet med myrjord ga de største tapene. I 1999/00 er det også målt svært høye jordtap i Grimestadbekken (730 kg/dekar) og Vasshaglona (140 kg/dekar). I Skuterud-, Mørdrebekken og Hotrankanalen var jordtapet ca 260 kg/dekar, mens det i Naurstadbekken og Vasshaglona lå jordtapene på ca 130 kg/dekar. Jordtapene fra Rømua var meget lave (60 kg/dekar) i 1999/00, sammenlignet med andre felt i tilsvarende områder. Kolstad-, Time- og Volbubekken hadde jordtap på ca 10 kg/dekar. Vannkvaliteten i jordbrukspåvirkede innsjøer er klassifisert i intervallet mindre god til meget dårlig.